Transmission shift control

ABSTRACT

A manual shift handle for a vehicle transmission is pivotally mounted on the steering column and extends to the left side thereof for operation by the left hand of the operator. This arrangement frees the operator&#39;&#39;s right hand for manipulation of hydraulic valve levers and the like. Fore and aft pivotal movement of the left hand shift handle will select the same transmission speeds or directions as would be selected by corresponding fore and aft movement of a standard right hand lever installed on the transmission control rod. This is achieved by a motion reversing mechanism between the left hand shift handle and the transmission control rod.

United States Patent 1191 1111 3,760,647

Ehrhardt Sept. 25', 1973 TRANSMISSION SHIFT CONTROL 3,417,635 12/1968Day et a]. 74/484 7 1 t B E 5] nven or Illenonle C hrhardt Park ForestPrimary Exammer Mllton Kaufman Att0meyCharles L. Schwab [73] Assignee:Allis-Chalmers Corporation,

Milwaukee, Wis. [57] ABSTRACT [22] Fil d; N 28, 1972 A manual shifthandle for a vehicle transmission is pivotally mounted on the steeringcolumn and extends to [21 1 Appl' 310l59 the left side thereof foroperation by the left hand of the operator. This arrangement frees theoperators right 52 11.5. C1 74/485, 74/473 sw hand for manipulation ofhydraulic valve levers and the [51] Int. Cl G05g 7/02 like- Fore and aftp l m vement of the left hand [58] Field of Sea h 74/485 484 473 SW,shift handle will select the same transmission speeds or 74/491 486, 473R directions as would be selected by corresponding fore and aft movementof a standard right hand lever in- [56] R f nce Cit d stalled on thetransmission control rod. This is achieved UNITED STATES PATENTS by amotion reversing mechanism between the left 309,125 12/1884 Best 74/491hand Shift handle and the transmlsslon control 2,694,943 1 1/1954Brumbaugh 74/473 R 4 Claims, 4 Drawing Figures Hill TRANSMISSION SHIFTCONTROL BACKGROUND OF THE INVENTION In material handling vehicles thecontrol levers for the hydraulic valves are normally placed at the rightside of the operators seat or at the right side of the control panel asviewed by the operator. It has heretofore also been customary to utilizea steering column transmission shift control lever which extends to theright of the steering column. Accordingly, when the operator wishes toshift the transmission and also operate the control valve for thematerial handling tool, he finds that it is only convenient to use hisright hand to accomplish both these functions. While the control valvelevers can be placed on the left side of the operator in some materialhandling vehicles, the right-handed operator prefers to operate thesecritical control components with his right hand because he feels moreconfident of exacting movement therewith.

BRIEF DESCRIPTION OF THE INVENTION In a material handling vehicle suchas a'lift truck, the transmission is controlled through a steeringcolumn transmission control mechanism which normally has the manual gearshift lever extending outwardly to the right of the steering column asviewed by the operator seated in the operator's seat. In the presentinvention, an alternate manual transmission control handle is mounted soas to extend to the left of the steering column, as viewed from theoperators seat, and a special motion reversing mechanism is employed totransmit pivotal movement of the alternate transmission control handleto the transmission control rod. In so doing, the forward movement ofthe alternate handle at the left side ofthe steering column will producethe same transmission adjustment as would be produced by the standardmanual gear shift lever attached to the transmission control rod andextending to the right of the steering column. This is desirable inorder togive the operator the same basic feel of the transmissioncontrol. By providing a shift handle extending from the leftside of thesteering wheel column, the operator will use his left hand to controlthe transmission, thereby leaving his right hand free to operate thecontrol levers for hydraulic valves and the like.

BRIEF DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION OF THE INVENTIONReferring to FIGS. 1 and 2, the lift truck 7' in which the presentinvention is incorporated includes a pair of rear steer wheels 12 and apair of front drive wheels 13 receiving power from an engine 8 through atransmission 9 and drive shaft 11. The truck 7 is provided with anoperators seat 14 at a central location on the truck and a control panel16 in front of the operators seat which includes an upstanding steeringcolumn 17 which in turn supports a steering wheel 18. A vertical mast 21is pivotally connected by means, not shown, at its lower end to theframe 15 of the truck 7 for swinging movement about a transverseaxisJSuch movement is effected by operation of a pair of hydraulic tiltjacks 22, one of which is shown. The mast 21 includes a verticallyreciprocatable carriage 23 on which a pair of lift forks 24 are mounted.The carriage 23 is raised and lowered by a lift jack, not shown, ofconventional construction. The lift jack and tilt jacks 22 arecontrolled by hydraulic valves operated by two of the manual controllevers 26 pivotally mounted on the right side of the operator as viewedin FIG. 2.

Heretofore, it has been customary to provide a steering columntransmission control mechanism with a manual control lever extendingfrom the right side of the steering column 17. In FIG. 4 such a controllever has been cut off with only a stub portion 41 remaining. Referringto FIGS. 1 and 3, the steering wheel l8'is connected to a steering shaft31 which extends downwardly through a tube 32 secured to a support block34 by a bracket 35 and cap screws 36. The lower end of the steeringshaft 31 is connected to suitable steering gear, not shown, forimparting steering motion to the steer wheels 12 upon rotation of thesteering wheel 18. The support block 34 is rigidly secured to thesteering column 17 by caps screws 37 and an inspection panel 40 isreleasably secured to the steering column 17 by releasable fasteningmeans 45. Referring also to FIG. 4, a transmission control rod 38 isdisposed in generally parallel relation to the steering shaft 31 and ispivotally supported in the support block 34 by a sleeve bearing 39. Thetransmission control rod 38 extends downwardly alongside the steeringshaft 31 and connects to appropriate transmission control valves, notshown, for the forward-reverse transmission 9. In the usual lift truckconstruction the transmission control rod 38 would have a manual shiftlever secured thereto for rotation therewith and extending outwardlylaterally to the right, as viewed in FIGS. 2, 3 and 4.

In accordance with the present invention an alternate manual shiftcontrol handle 43 is provided which extends laterally to the left of thesteering column 17. In this position the shift control handle 43 may beoperated with the left hand, thereby freeing the right hand foroperation of the control levers 26. This not only makes it moreconvenient to operate the truck and its controls, but increases thespeed and efficiency of operation of the various lift truck operations.The manual shift handle 43 extends downwardly through an opening in atop plate 44 and is pivotally connected to and supported by the supportblock 34 through a suitable sleeve bearing 45. The lower end of themanual shift handle 43 carries a sleeve 46 secured thereto by a pin 47which is disposed in transversely spaced relation to a sleeve 51 securedto the transmission control rod by a pin 52. A pivotal motion reversingmeans'is interposed between the'manual control lever 43 and thetransmission control rod 38 in'the form of a pair of intermeshing parts56, 57 which are secured by welding to the sleeves 46, 51. The parts 56,57 extend transversely toward one another and have ends which intermeshto transmit pivotal motion. In the illustrated embodiment of this motionreversing mechanism, a generally vertically disposed pin 61 is press fitin a drilled opening 62 adjacent the free end of the part 56 and thefree end of the part 57 has walls defining an open ended slot or groove63 which is dimensioned to receive the upstanding pin 61. This pivotalmotion reversing mechanism may be considered to be a tongue and groovetype connection wherein the pin 61 constitutes the tongue element andthe groove 63 constitutes the groove element. As clearly shown in FIG.4, the parts 56, 57 are juxtaposed one above the other.

From the foregoing description of the present invention, it is apparentthat a novel transmission control handle is provided which extends fromthe left side of the steering console or column 17 thereby freeing theoperators right hand for manipulation of the control valve levers 26.The pivotal motion reversing mechanism comprising parts 56, 57 allowsthe handle 43 to move the control rod 38 for the transmission in thesame pivotal direction as it would be moved by corresponding fore andaft movement of the conventional transmission control handle if attachedto part 41. This optional left hand control gives the operator the samedirectional feel as the usual right hand control.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

l. A steering column transmission control mechanism for a motor vehiclecomprising:

a steering shaft a fixed support for said steering shaft,

a transmission control rod rotatably mounted on said support alongsidesaid steering shaft and adapted for connection to a manual transmissioncontrol lever extending laterally therefrom at one transverse side ofsaid support,

a manual transmission shift control handle pivotally connected to saidsupport and extending laterally outward at the other transverse side ofsaid support, and

pivotal motion reversing means interconnecting said control handle andsaid control rod.

2. The invention of claim 1 wherein said pivotal motion reversing meansincludes a first part rigidly secured to said handle and extendingtoward said control rod and a second part rigidly secured to saidcontrol rod and extending toward said handle, said first and secondparts having intermeshing ends thereon operable to cause said controlrod to pivot in one direction of rotation on pivotal movement of saidhandle in the opposite direction of rotation.

3. The invention of claim 2 wherein one of said intermeshing endspresents a groove and the other of said intermeshing ends presents atongue extending into and in motion transmitting engagement with saidgroove.

4. The invention of claim 3 wherein said parts are positioned one abovethe other and said tongue is a pin extending into said groove.

1. A steering column transmission control mechanism for a motor vehiclecomprising: a steering shaft a fixed support for said steering shaft, atransmission control rod rotatably mounted on said support alongsidesaid steering shaft and adapted for connection to a manual transmissioncontrol lever extending laterally therefrom at one transverse side ofsaid support, a manual transmission shift control handle pivotallyconnected to said support and extending laterally outward at the othertransverse side of said support, and pivotal motion reversing meansinterconnecting said control handle and said control rod.
 2. Theinvention of claim 1 wherein said pivotal motion reversing meansincludes a first part rigidly secured to said handle and extendingtoward said control rod and a second part rigidly secured to saidcontrol rod and extending toward said handle, said first and secondparts having intermeshing ends thereon operable to cause said controlrod to pivot in one direction of rotation on pivotal movement of saidhandle in the opposite direction of rotation.
 3. The invention of claim2 wherein one of said intermeshing ends presents a groove and the otherof said intermeshing ends presents a tongue extending into and in motiontransmitting engagement with said groove.
 4. The invention of claim 3wherein said parts are positioned one above the other and said tongue isa pin extending into said groove.